I've been making use of out of spec parts to hack together a 4x12 buckling spring board.
The goal is to create a moderately repeatable NKRO build with a Teensy so my fingers can gently caress buckling springs without horizontal stagger tunneling my carpals.
So far I've proofed two concepts; firmware reads the signal off the membrane contact without the weird paddle debounce becoming an issue (even if the contact has a little resistance from the carbon contact coating), and the membrane makes reliable contact with metal (I was concerned it would be harder with non silver epoxy).
From here, I've started a POC build on a standard steel backplate using the original mylar (so no nkro), and testing if I can reliably connect to the pressure-contact leads that normally go to the controller board. After MUCH fiddling, the top half works so long as I hold my face just right. Getting even pressure for the contacts was terrible. Binder clips are strong and look straight, but they're not
. I think I'm just going to hijack the connections off the circuit board using the standard compression fitting within the case.
The bottom half is (technically) easier to connect to, because the connection points are further apart, and don't have that carbon contact coating on them.
The endgame is to design a circuit board that will serve as the bottom layer of mylar, to receive the connections from the top layer. By shorting two top 2x12 layers of mylar, I can get two logical rows out of them, and then make a 2x24 matrix that will fit onto a Teensy++ 2.0. Shorting the mylar also simplifies making reliable connection to the sheet. The circuit board will also allow diodes to be easily mounted for NKRO, while lending rigidity to the frame barrel assemblies to be screwed into.
